Scratchpad
Markdown
Preview
Sandboxed · scripts off · offline
Tools
Markdown
Browser tool · local only
Open or draft a UTF-8 text or code file, then download it when you are done. Markdown and HTML can be previewed side by side. Python gets a shell under the editor, sharing one interpreter with Run. Unknown text formats open as plain text. Nothing you type is uploaded. Copy link packs the file into the link itself, so anyone holding that link holds the text.
Files are decoded and downloaded as UTF-8. Markdown and HTML render in a sandboxed frame with scripts disabled, and it cannot reach the network, so remote images and stylesheets do not load. An open preview can be printed, or saved as PDF from the print dialog, in black on white. Python runs on Pyodide, a build of CPython 3.14 for WebAssembly, in a worker on your own machine: the standard library is there, the file never leaves the browser, and no server runs anything. The editor and the shell share one interpreter. Run restarts it and executes the file, so when it stops you can inspect what it defined from the prompt, and anything you define at the prompt is gone the next time you Run. The runtime is a 12 MB download the first time you use it in a session, served from this site rather than a CDN, and cached by the browser afterwards. Stop shuts the worker down, which is also how you end an infinite loop; Restart clears the names without reloading the runtime. input() works: the program pauses, you type a line into the shell and press Enter, and Ctrl+D ends the input instead. That needs shared memory, which browsers only allow on a cross-origin-isolated page, so this one route sends the two headers that ask for it; if a browser withholds it, everything except input() still works and the shell says so. Third-party packages are not installed, and code only ever runs when you ask, never on opening a file or a link. Other syntaxes are highlighted but never executed. A share link carries the whole file compressed into the part of the URL after the # sign, which browsers never send to a server, so the text still reaches nobody but the person you hand the link to. Treat the link as you would the file: do not put anything confidential in one, and expect long files to be refused because chat clients and mail programs truncate long URLs.